Prophylactic Radio-Frequency Ablation (RFA) before an Implantable Cardioverter Defibrillator (ICD): a case series

Dr Deep Chandh Raja!, Dr Ulhas M. Pandurangi2, Dr Rajeev Pathak3

1- Clinical Cardiac Electrophysiology Fellow, Australian National University, Canberra; 2- Chief of Dept’ of EP & Pacing, The Madras Medical Mission, India;

3- Clinical Lead of Cardiac Electrophysiology, The Canberra Hospitals, Canberra, ACT

INTRODUCTION- Catheter ablation for management of VT is CLASS IIb (ACC 2017)- Only a handful of trials studying role of ‘Prophylactic RFA before ICD implant’- SMASH VT, VTACH, SMS< VISTA, HELP VT, VANISH- None show mortality benefit; However promise towards reduction in ICD shocks

METHODOLOGY

Patients with ICD indications

RFA Catheter ablation: Substrate mapping & Homogenisation

ICD + AAD ± Remote monitoring

Case study: 69 Y, M, ICMPModerate LV dysfunction LVEF 33%; Presents with resuscitated cardiac arrest

STEP 1: EP STUDY+ RFA

STEP 2: ICD Implant

REFERENCESAtti V et al. Prophylactic catheter ablation of ventricular tachycardia in ischemic cardiomyopathy: a systematic review. JICE https://doi.org/10.1007/s10840-018-0376-5

CLINICAL IMPLICATIONS- Maintenance of National ICD registry- multi-center pooling of data - May derive enough numbers to suggest benefit of RFA before ICD implant- A National Multi-Center Randomised Control Trial: to study role of RFA before ICD Implant for secondary prevention

Our retrospective data, though small, reveals significantly lesser number of ICD therapies (shocks or ATPs) post-ICD implant in patients for a documented VT/VF who also received a prophylactic RFA.

CONCLUSION

RESULTSGROUP A: RFA followed by ICD GROUP B: ICD

142

Primary prevention

Secondary prevention

3727

Primary prevention

Secondary prevention

Absolute risk reduction= 34%

Relative risk reduction= 54%

NNT=2.9

SECONDARY PREVENTION

GROUP A

(n= 42)

GROUP B(n= 27)

P VALUE

SHOCK 9 (21.4%)

11 (40.7%) 0.08

ATP 8 (19%) 9 (33%) 0.17

NO OF PATIENTS WITH

EPISODE (SHOCK/ ATP)

17 (40%) 20 (74%) 0.006

GROUP A GROUP B P VALUE

Mean no. of Shocks

0.37±0.8 1.2±3 0.055

Mean ATP 0.7±3 2±11 0.43

Mean Therapies

1.1±3.2 2.7±13 0.42